Appointment synchronization with Google Calendar

[christophpickl]

synchronize gcal events. import (locally add), delete (locally delete) and update (from gcal to local). so for sync, its one way, gcal always wins. when changing an appointment (add/update/delete) while having an internet connection, all changes will be propagated to gcal.

NO support yet for OFFLINE working...

implement some client suggesting component, when reading appointment title and map to existing client (string comparison functionality).

• [x] sync logic
• [x] sync report view
• [x] import logic

[christophpickl]

i'm afraid this might not work with the first shot... be brave.